Method of and apparatus for coating wires and cables.



L. W. GHUBB. METHOD OF AND APPARATUS FOR COATING WIRES AND GABLES.

APPLICATION FILED JUNE 25, 1907. RENEWED NOV. 17, 1911.

1,068,411 3. Patented July 29, 1913.

2 SHEETS-SHEET 1 JEBigx f W!TNESSES: INVENTOR ATTdRNEY L. W. CHUBB.

METHOD OF AND APPARATUS FOR COATING WIRES AND GABLES.

APPLICATION FILED JUNE 25, 1907. RENEWED NOV. 17, 1911.

1,068,41 3. Patented July 29, 1913.

2 SHEETSSHEET 2.

WITNESSES: INVENTOR ATTORNEY U ITED STATES PATENT OFFICE.

LEWI ES W. CHUBB, OF WILKINSBUBG, PENNSYLVANIA, ABSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFKOTUBING COMPANY, A CORPORATION OF PENNSYLVANIA.

METHOD OF AND APPARATUS FOR COATING TIRES AND CABLES.

Specification of Letters Patent.

Application filed June 25, 1907, Serial No. 380,709. Renewed November 17, 1911. Serial No. 660,910.

To all whom it may concern: l

lie it known that I, LEWIS W. Cumin, a citizen of the United States, and a residentof Wilkinsburg, in-the county of Allegheny and State. of Pennsylvania, have invented a new and useful Improvement in Methods of and Apparatus for Coating Wines and Cables, of which the following is a specification.

My invention relates to methods of and apparatus for coating wires and other electrical conductors, and ithas for its ob ect to provide an effective method and apparatus whereby a very thin insulating coat: ing may be readily and continuously applied to wires which are to be used in the construction of coils for electrical apparatus.

In the manufacture of small motors and other electrical apparatus, large quantities of small gage wire having cotton or silk insulating coverings have heretofore been employed. In order to materially lessen the expense of insulating such conductors and also to provide an insulating. covering that shall occupy less space, I have devised the method and apparatus herein set forth.

Itis a well known fact that an electrolytic valve action may be produced in a cell comprising plates of aluminum, copper, cobalt and a few other metalswhen immersed in a suitable liquid, such as a solution of ammonium bora te or a solution of borax, and, furthermore, it has been found by repeated tests that the plate which acts as a valve will readily permit the flow of an electric currentat. av voltage only slightly above apredetermined amount while it will act as a substantially perfect barrier to currents at a less voltage. This predetermined voltage is dependent upon the material of which a plate is constructed and the solution in which the film is electrolytically produced. contain metals, when treated in the some way, are capable of resisting only relatively low voltages, aluminum, under the same conditions, will'become coated with an insulating film, capable of resisting relatively high voltages.

By utilizing the principle of the electrolytic valve, I provide, according to my present invention, a method and an apparatus involving the use of alternating current electrical energy tor continuously producing very thin insulating films on the surfaces of aluminum wires and other conducillustrating a modified form of apparatus for accomplishing the same results. I

Rcferring to Figs. 1 and 2 of the drawings, a bath 1 of ammonium borate, or other liquid capableof producing an electrolytic valve action in connection with aluminum and other metals, is contained in a suitable tank or vessel 2. Au alternating current transformer 3 having acore member 4, aprimary winding 5, and secondary windings 6 and 7, is partially immersed in the batlrl, the primary and secondary windings 5, 6, and 7 being preferably located on a portion of the core member 4 which is not immersed in the liquid. The primary winding 5 of the transformer 3 is supplied with energy from a generator 8, or other suitable source, the secondary windings 6 and 7 being interconnected and having their free terminals respectively connected, by brushes 9 and 10, to metal drums or pulleys 11 and 12. Two aluminum wines or cables 13 and 14 are fed from s or bobbins 15 and 16, over pulleys l7 and 18 and drums l1 and 12, into the bath 1. A non-conducting barrier or partition 18' may preferably be adapted to prevent the formation of short-.circuited transformer secondary paths through the liquid. The conductom are guided around the submerged or partially submerged portionof the cone member 4, forming several turns of secondary windings which are respectively connected in series with the windings 6 and 7, two .gnomps of insulating pullcys Hand 20 acting as guides for the wires as they pass through the bath. The wires are finally passed out of the bath and onto a pair of gathering reels 21.

Referring to Figs. 3 and 4, in which similar par-ts are designated by the same nefcnence numerals as those of Figs. 1 and 2,

a. substanhially rectangular cone member 22,

having a cross leg 23, is supported by a Patented July 29, 1.913. I

shoulder 24 formed on a tank 25 which contains the bath 1. A channel partition 26 serves to keep the liquid aw ay from the leg 2 but does not interfere with the free move-- meut of the conductors 13 and 14 as they pass through the bath and around the transformer leg. The transformer may be provided with primary and secondary windings, as shown in Figs. 1 and 2, or a single winding 27 may be employed, as shown in Figs. 3 and 4. In the latter arrangement, the turns provided by the moving conductors form additions to the main winding of the auto-transformer. Sheet tin or other sheet metal may be used in forming the con taining tank 25, since its relation to the core member 22 is such as to avoid wasteful secondary transformer circuits. Since the in: sulat-ing films that are formed on the sur* faces of conductors by the electrolytic action which takes place when they are passed through suitable baths is not injured by the passage of electric current through it into the wire, it is feasible to arrange a system, as above indicated, in which alternating current is employed as a means for producing the electrolytic action.

It has been observed that when an abnormally high voltage is applied to a bare wire before it passes into the bath, considerable heating and sparking take place at the surface of the liquid, and one of the principal advantages in my improved system arises from the fact that a moderate voltage may be impressed upon the wires before they enter the bath, while the additional turns formed by the passage of the wire around the submerged'leg of the transformer makes a greater difference of potential between the two conductors before they leave the bath, and, consequently, the electrolytic action is more effective in producing the insulating film upon the surface of the wires. Another advantage in my present system arises from the fact that only a single bath is necessary and, at the same time, two conductors maybe continuously supplied with insulating coatings as they are passed therethrough. It is to be understood that modifications may be effected in the system, without departing from the spirit of my invention, and I desire that only such limitations shall be imposed as are indicated in the appended claims.

establishing an electric circuit through th conductors and the bath.

3. The combination with a suitable bath, a transformer comprising primary and secondary windings and a core member partially submerged in the bath, and a source of alternating current, connected to the primary winding, of means for passing conductors through the bath and around the submerged portion of the core and means for establishing a secondary circuit through the conductors and the bath.

4. The combination with a bath of ammonium bor'ate solution or other suitable liquid capable of producing an electrolytic valve action, a transformer comprising primary and secondary windings and a core member partially submerged in the bath, of means for passing conductors around the submerged portion of the transformer core and establishing an electric circuit through the,

conductors and the bath.

5. The combination with a suitable bath, a transformer comprising primary and secondary windings and a core member which is at least partially submerged in the bath, and a source of alternating current energy connected to the primary winding, of means for so passing a pair of independent conductors through the bath as to produce two groups of turns around the core, and sheaves or pulleys of conducting material severally connected to the conductors before they enter the bath and also connected to the free terminals of the secondary winding.

6. The combination with a bath of am monium borate, a transformer comprising primary and secondary windings and a core member which is at least partially submerged in the bath, and a source of alternating current energy connected to the primary winding, of means for so passing a pair of independent conductors through the bath as to produce two groups of turns around the transformer core, and sheaves or pulleys of conducting material severally connected to the conductors before they enter the bath and also connected to the free terminal of the secondary winding.

7. In a transformer, the combination with a stationary core -member, of a winding therefor comprising a stationary coil and a plurality of convolutions of continuously moving conductors connected in series therewith.

8. In a transformer, the combination with a core member, primary and secondary Windings, and a source of alternating current energy connected to the primary winding, of means forpassingconductors around the core member in inductive relation therewith.

9. The method of coating a conducting wire with insulation which consists in subjecting successive lengths thereof to the action of a liquidbath and simultaneously passing an alternating electric current therethrough.

10. The method of coating a conducting wire with insulation which consists in moving it continuousl through a liquid bath and simultaneous y subjecting it to the action of an alternating electric current.

11. The method of'coating a conducting wire with insulating materlal which consists in subjecting successive lengths thereof to the act-ion of a liquid bath and simultaneously subjecting the submerged wire to the action of alternating electric currents both directly and by induction. v

12. The method of coating a conducting wire with insulating materlal which consists in submerging successive lengths thereof in a liquid bath and simultaneously subjecting the submerged Wire to the ind'uctive action of an alternating electric current.

13. The method of coating a conductin wire with insulation which consists in e fecting movement of the wire through a liquid bath and simultaneously energizing 25 it by alternating current energy.

14. The method of'coating an alumlnum Wire with insulation which consists in effecting movement of the wire contmuously through a liquid bath and simultaneously energizing it by alternating current energy.

In testimony whereof I have hereunto subscribed my name this 20th day of June,

LEWIS W. CHUBB. Witnesses R. D. DE WOLF, BIRNEY HINES. 

